Tag: metals

Quizzes (9) Questions (306)

Questions Related to metals

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Potassium on exposure to air gives:

  1. Potassium peroxide

  2. Potassium superoxide

  3. Potassium dioxide

  4. Potassium oxide
Reveal answer Fill a bubble to check yourself
A,B,D Correct answer
Explanation

Potassium is an extremely active metal that reacts violently with oxygen in air. Potassium oxidizes faster than most metals and forms oxides with oxygen-oxygen bonds. Three species are formed during the reaction: potassium oxide, potassium peroxide, and potassium superoxide.

$8K + 4O _2 \rightarrow 2K _2O + 2KO _2 + K _2O _2$

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Four metals $P$, $Q$, $R$ and $S$ react with water as given below:
I. $P$ reacts with cold water
II. $Q$ reacts with hot water
III. $R$ reacts with steam
IV. Red hot $S$ reacts with steam.
Then, highly reactive metal is:

  1. $P$
  2. $Q$
  3. $R$
  4. $S$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The highly reactive metal is $P$ as it reacts with cold water. This is because, the reaction with cold water requires lowest energy of activation.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Select the object from the following which can shine (have lusture) _____________

  1. glass bowl and wooden bowls

  2. towel and toys

  3. shirts and scarfs

  4. ornaments and brass utensils
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

1) ornaments and brass utensils both are made up of metals.

2) Metals are lustrous because of the free electrons they have.

3) The free electrons can move freely in the metal causing any light incident on them to get reflected back.

4) This reflection is specular reflection rather than diffused and thus the metal surface appears shiny or lustrous.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Metallic radii of some transition elements are given below. Which of these elements will have the highest density?
Element                    $Fe$     $CO$       $Ni$     $Cu$ 
Metallic radii/pm     126     125     125    128

  1. same

  2. $Ni$
  3. $Co$
  4. $Cu$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Density is mass divided by volume. For transition elements in the same period, as atomic number increases, the atomic radius generally decreases or stays similar, while the atomic mass increases significantly. Copper (Cu) has the highest atomic mass among the listed elements (Fe, Co, Ni, Cu), leading to the highest density.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which one of the following four metals would be displaced from the solution of its salt by other three metals?

  1. Mg

  2. Ag

  3. Zn

  4. Cu
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ag metal would be displaced from the solution of its salt by Mg, Zn or Cu metals.

Among the given metals, the standard reduction potential for the half reaction $\displaystyle Ag^+ + e^- \rightarrow Ag$ is maximum.

Hence, among the given metals (ions),  $\displaystyle Ag^+ $ ion has maximum strength as oxidising agent. Hence, $\displaystyle Ag^+$ ion gains an electron and other metals loses electron.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Read the following statements and answer as true or false.
The presence of carbon in pig iron makes it brittle.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Pig iron has a very high carbon content, typically 3.8–4.7%, along with silica and other constituents of dross, which makes it very brittle, and not useful directly as a material except for limited applications.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which of the following is not correct observation based on Ellingham diagram?

  1. A metal can reduce the oxide of other metal which lies above it in Ellingham diagram
  2. $CO$ is more effective than $C$ as reducing agent below $170^{o}C$
  3. $\Delta G^{o}$ metal oxide is higher than of $CO _{2}$ hence oxidation of metal sulphides to oxides is not favourable

  4. Need for conversion of metal sulphide to metal oxide before reduction can be explained thermodynamically
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

As moving down of bottom of diagram metals becomes more reactive oxides will be hard to reduce.A given metal can reduce the oxides of other metal which lies above it in Ellingham diagram.

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Which of the following are properties of non-metals?

  1. Lustre

  2. Can form alloys

  3. Amorphous

  4. Non-conductive towards electricity
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

The properties of non-metals are:

  1. They are amorphous in nature.
  2. They are not malleable and ductile.
  3. They are poor conductors of heat and electricity.
  4. They do not form alloys.

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Which non-metal has a shining surface?

  1. Graphite

  2. Phosphorous

  3. Sulphur

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Graphite is the most stable form of carbon and so it is used as the standard state for defining the heat and formation of carbon compounds. It has a layered planar structure and the bonding between the layers is vander waals bonds. It is a non metal with shining surface.